In the United States, injuries to passengers involved in

Premise: In the United States, injuries to passengers involved in automobile accidents are typically more severe than in Europe, where laws require a different kind of safety belt.
Conclusion: United States needs to adopt more stringent standards for safety belt design to protect automobile passengers better.

Option A - Incorrect
This claim is not true as we cannot know from the passage if Europeans are more likely to wear safety belts than the people in the United States. It, therefore, weakens the argument.

Option B - Incorrect
The training received by the European drivers do not determine the injuries suffered by themselves or their passengers because it's clear from the passage that safety belts which the law requires, plays a vital role in the level of accidents.

Option C - Incorrect
This is irrelevant and out of point. The sturdy construction of cars in Europe or the United States does not conform with the argument.

Option D - Correct
This claim strengthens the argument because European law requires a different kind of safety belt, unlike the United States law. As a result of this, automobile passengers in the United States have a greater chance of being involved in automobile accidents than those in Europe.

Option E - Incorrect
This argument is not concerned with states that have adopted the using of safety belts for passengers, neither was it on if the states experience no reduction in the average severity of injuries suffered by passengers in automobile accidents. This claim do not relate to the argument in question. Thus, it weakens the argument.

Thanks. I hope this helps.